Financial Model Interview Round

Hi all, just finished an interview round and was stumped by the following.

For this round, the general skeleton of the financial model was provided and we just had to fill up and link everything. Let's assume a forecast period of 2023E - 2028E. The different schedules and 3FS were fine till I got to the valuation portion, where we had to calculate the WACC.

Even though we were provided the cost of debt and the various components to calculate cost of equity (ie. beta, risk free rate and so on), I was a bit confused as to what capital structure to use as my weights for debt/equity; do I:

1) Use the current capital structure (book value of equity and debt at the end of 2022 from the balance sheet), or; 2) Use the capital structure at the end of the forecast period (balance sheet values at the end of 2028).

From the skeleton provided, it looked like they only wanted us to calculate one WACC value and not use a different one every year.

Another issue was they did not provide any market values and we only have the balance sheet. Book value of debt is simple to retrieve, but for book value of equity, do I just use share capital or do I also have to add other equity accounts (ie. retained earnings)?

Thank you!